The present invention relates to orthopedic devices for supporting body portions and a method of fitting these devices. More particularly, the invention relates to inexpensive, easily formed, removable casts, braces or supports which provides comfortable patient fitting as well as providing better support and stability than previously available removable orthopedic supports.
Numerous materials have been used or proposed for orthopedic casts, splints, and braces. The conventional material is Plaster of Paris. Mixtures of Plaster of Paris and water are formable and moldable when wet but harden upon drying. Other materials which have been used for orthopedic supports include numerous synthetic resins, e.g., plastics. Some of these synthetic materials are soft for shaping and forming until subjected to a liquid polymer cure while others may cured by subjection to ultra-violet radiation. A large family of synthetic resins are thermoplastic; that is, they may be heat-softened and harden upon cooling. The following United States patents are examples of the orthopedic device art:
______________________________________ U.S. Pat. No. Patentee ______________________________________ 2,759,475 Van Swaay 2,781,757 Hauser et al. 2,800,129 Van Swaay 3,089,486 Pike 3,302,642 Allen 3,490,444 Larson 3,501,427 Edenbaum 3,662,057 Webster et al. 3,819,796 Webster et al. 3,998,219 Mercer et al. 4,006,741 Arluck 4,019,505 Wartman 4,226,230 Potts ______________________________________
The materials used for previous orthopedic devices such as casts, splints, and braces have significant shortcomings. For example, Plaster of Paris is inconvenient to use because it undergoes irreversible hardening and hence cannot be reformed. Casts made with Plaster of Paris are heavy and bulky, yet the material crumbles readily. Further, supports made of Plaster of Paris generally cannot be readily removed and replaced. Hence bathing with a Plaster of Paris cast causes problems because the plaster deteriorates when wet.
Other materials which have been used to form orthopedic supports also have physical properties which make them undesirable. For example, mixing of plastics to obtain polymerization for proper hardening often requires considerable care and undesirable clean-up. A number of materials are not easily moldable while others require cumbersome wrappings, e.g., with bandages, thereby prohibiting easy removal for bathing or comfort purposes.
Some previously used materials have additional difficulties because of insufficient strength, brittleness, dimensional instability, or lack of thermal softening satisfactory for forming directly on a limb or other body member to be supported. Many of the thermoplastic materials which have been suggested for use in orthopedic devices require molding temperatures so high that bulky, cumbersome thermal padding must be used to prevent damage to the skin.
Many other materials that are thermomoldable at lower temperatures lose their dimensional stability at too low a temperature to be useful. For example, one currently used brace, tradenamed WARM'N FORM, uses a thermoplastic sandwich such as disclosed in the Arluck U.S. Pat. No. 4,006,741. This thermoplastic sandwich can be molded simply by immersing in a hot water bath. This type of heating obviates the potential problem of blistering skin caused by too high a temperature but this brace has the problem that if it is left in a car on a hot day, the support member loses all dimensional stability and has to be remolded to conform to the body contours. This device also lacks sufficient structural support to properly protect the body portion.
Accordingly, an object of the invention is to provide an improved orthopedic device for protecting and supporting body portions such as limbs or torso. Another object of the invention is to provide an orthopedic device for supporting body portions which is easily fitted and moldable upon the patient without danger of injury. A further object of the invention is to provide a process for fitting an orthopedic device to a body portion which is quick, easy, and requires as little manipulation of the patient as possible. Fitting the device to the body portion in this manner is more comfortable for the patient and allows braces or other supports to be fitted and reformed as needed by lab technicians.
Other specific objects of the invention include the attainment of an orthopedic splint, brace, cast or like support that is easy to form, that can be thermoformed directly on the limb or other body portion to be supported after softening by dry heat, that can be formed with a relatively high degree of cleanliness and hence requires little clean-up, that is readily softened and may be resoftened to improve fit or accomodate changes in size of the body portion due to swelling, that is relatively comfortable for the patient to wear because of its light weight and proper support, that has a relatively high degree of dimensional stability after forming, that is sufficiently strong to resist crumbling, cracking, abrasion, and like breakage, that can be formed for relatively easy temporary removal and subsequent replacement, and that is highly resistant to water damage. Materials forming the orthopedic support should be compatible for long term contact with the patient. The orthopedic device of the present invention is versatile enough that it can be used to support almost any body portion, e.g., limbs or torso, yet is inexpensive and easy to mold.
Other objects and features of the invention will be apparent from the drawing and the following description.